Decarboxylation, that is, elimination of the --COOH group as CO.sub.2, is a known process. March, J., Advanced Organic Chemistry: Reactions, Mechanisms, and Structure, 1968, pp. 453-436, 477-480 and 878-879, describes various decarboxylation reactions. At pages 435-436, it is stated that aromatic acids can be decarboxylated by heating with copper and quinoline. At pages 477-480, it is stated that aliphatic acids which undergo successful decarboxylation have certain functional groups or double or triple bonds in the alpha or beta positions such as malonic acids, alpha-cyano acids, alpha-nitro acids, alpha-aryl acids, alpha-keto acids, alpha-trihalo acids, beta-keto acids, beta,gamma-olefinic acids and the like. At pages 878-879, oxidative decarboxylation is described in which lead tetraacetate cleaves carboxyl groups, replacing them with acetoxy groups, which may be hydrolyzed to hydroxyl groups. It is stated that compounds containing carboxyl groups on adjacent carbons (succinic acid derivatives) can be bisdecarboxylated with lead tetraacetate. It is also stated that compounds containing geminal carboxyl groups (malonic acid derivatives) can be biscarboxylated with lead tetraacetate, gem-diacetates (acylals) being produced, which are hydrolyzable to ketones.
Enichem Synthesis SpA, Dimethyl Carbonate Product Bulletin, pp. 10-13, discloses the reaction of aromatic amines with dimethyl carbonate to give N-methyl and N,N'-dimethyl aromatic amines. It is stated that the reaction is carried out under the same conditions as used for the methylation of phenols. The reaction of phenols with dimethyl carbonate is carried out in the presence of a basic catalyst such as NaOH, Na.sub.2 CO.sub.3, NaOCH.sub.3, tertiary amines and heterocyclic nitrogenous compounds. Reaction temperatures of at least 140.degree. C. are required. It is stated that the speed of reaction can be accelerated with catalytic quantities of organic and inorganic halides. At page 12, it is stated that dimethyl carbonate reacts with amines (aliphatic or aromatic, primary or secondary) to Produce carbamates and ureas. At page 13, it is stated that aminoalcohols can react with dimethyl carbonate in the presence of sodium or potassium alkoxides to yield 2-oxazolidinones.
Dow Chemical U.S.A., Experimental Ethylene Carbonate XAS-1666.00L Product Bulletin (1982), pp. 5-7, discloses that aromatic amines can be reacted with ethylene carbonate to form N-(2-hydroxyethyl) derivatives. It is stated that with primary amines such as aniline, a mixture of mono- and di-substituted derivatives can be prepared. It is also stated that carbamates and imidazolidinones can be produced through the reaction of ethylene carbonate with aliphatic mono- and diamines.
Texaco Chemical Company, TEXACAR.RTM. Ethylene and Propylene Carbonates Product Bulletin (1987), pp. 22-23, describes the reaction of ethylene carbonate and propylene carbonate with primary and secondary aliphatic amines at low temperatures to yield carbamates. It is stated that ethylene carbonate and propylene carbonate can react with amines to give the corresponding hydroxyethyl and hydroxypropyl derivatives.
Trotta, F. et al., J. Org. Chem. 1987, 52, pp. 1300-1304, relates to selective mono-N-alkylation of aromatic amines by dialkyl carbonate under gas-liquid phase-transfer catalysis conditions (continuous flow process). The catalyst is a polyethylene glycol in the presence of a base (K.sub.2 CO.sub.3).